A conventional rotary type valve device has a shaft, and a valve body, a housing, and a seal portion.
First of all, the shaft is rotated and driven by output of a motor or the like, and the valve body rotates integrally with the shaft and is provided with at least a part of a cylindrical surface on an outer peripheral surface. The housing has a valve chamber, in which the valve body is rotatably accommodated, and the valve chamber has a valve opening which is opened or closed by the valve body.
The seal portion is configured to maintain a closure of the passage when the valve opening is fully closed, and a valve body side seal on a side of the valve body is in contact with a housing side seal on a side of the housing such that the closure of the passage is maintained (see, Japanese Patent Publication No. 2013-44415 referred to as a patent document 1).
However, in the valve device of the patent document 1, further improvement is necessary regarding a holding of the shaft with high accuracy and a securing of a seal surface accuracy at a low cost.